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An anonymous reader writes with this quote from the BBC:
"Rocket entrepreneur Elon Musk believes he can get the cost of a round trip to Mars down to about half a million dollars. The SpaceX CEO says he has finally worked out how to do it, and told the BBC he would reveal further details later this year or early in 2013. ... 'My vision is for a fully reusable rocket transport system between Earth and Mars that is able to re-fuel on Mars — this is very important — so you don't have to carry the return fuel when you go there,' he said. 'The whole system [must be] reusable — nothing is thrown away. That's very important because then you're just down to the cost of the propellant.' ... He conceded the figure was unlikely to be the opening price — rather, the cost of a ticket on a mature system that had been operating for about a decade. Nonetheless, Musk thought such an offering could be introduced in 10 years at best, and 15 at worst."

Did he launch them in falcon 9 last time?I mean spaceX is awesome, but he really should have more realistic look on things.Please first make a human rated space capsule, and actually start launching stuff from its long manifest,then we will talk mars

As the Rogers Commission report showed, NASA management held that the shuttle would catastrophically fail about 1 out of every 100,000 flights, which is a ridiculous figure. The engineers more realistically put it between 1 out of every 100 flights and 1 out of every 50. Reality put it at about 1 out of every 68 flights. I'm not sure what the human-rating requirements were before the two shuttle disasters, but the current standards are 1 catastrophe in every 500 ascents and 1 in every 500 descents, so the

I guess a whole lot is going to be riding on this next Falcon 9 launch. If it blows up on the launch pad I would think you might be right. Somehow I doubt that will happen, but who knows?

The problem with your reasoning is that Elon Musk is launching stuff into space and building real spacecraft, hiring real astronauts and getting stuff done. He also has that "crew-rated space capsule" and has even done the math to get it to Mars. In terms of the "long manifest", they are paying deposits to get onto that list, so there must be some actual people with money who are willing to spend several million dollars risking that something is going to happen.

I agree that SpaceX needs to go through the manifest, but Elon Musk does seem like he is able to deliver on his promises.

In the U.S. Navy, the only thing that forces a submarine to surface is strictly food, as the spaces aboard ship are too small for them to grow it. Six to nine month deployments where they stay underwater the whole time are even pretty common. In other words, your analogy is sort of flawed here. Yes, they can surface... but doing so compromises their mission and that is something they won't do.

In terms of gravity, spinning a spacecraft can do wonders. You want to keep the spin rate below about 1 RPM, but that merely implies the size of the vehicle or the length of the tether to the counter weight. That isn't being done on the ISS because.... it has been proposed as a possible module and was even one of the original module designs. It was cut for pure political reasons, not technical ones.

As for radiation, a tank of water does wonders to stop just about all hazardous radiation you would encounter in space. You might need to hunker down in some reserved spaces for a few days when a solar flare goes by, but it isn't impossible to cope with or to even predict when it happens. The Space Weather Prediction Center [noaa.gov] already exists to do forecasts for solar storms, where I'm pretty sure more resources would be put into trying to make more accurate predictions for manned spaceflight.

In terms of the vacuum of space, 30 m of water is the same pressure difference as going from sea level to space. On top of that, it is a whole lot easier to build something to keep pressure in (like a balloon) than to keep the pressure on the outside from crushing you. Spacesuits are more complicated because you want to bend that balloon to make it useful, but that is also a solved engineering problem based upon suits of armor fabricated at the time of Henry VIII of England.

As for extremes in temperature, it isn't that big of a deal either. Space is a very good insulator and the largest problem you have is simply getting rid of excess heat as you need to radiate it away as convection isn't an option. To keep a spacecraft from getting too hot one one side, rotating the vehicle is again key, something almost all satellites use even now much less manned vehicles.

I'm not saying that the issues you are complaining about are invalid, but it is something that there is experience and knowledge on how to accomplish them, where the largest factor in their use is simply getting them into space in the first place as launches to LEO have been so expensive in the past. When a liter of water costs $100k or sometimes more to put it into space, weird sorts of attitudes about what is important start to happen with spacecraft designs. Elon Musk is suggesting he might get that below $500 or perhaps even less with these reusable spacecraft, which is partly where the $500k per person round trip to Mars comes from.

10 years ago, Musk said that he wanted to make multiple rockets that were cheap to launch. His point was that launch was not about capability, but about economics. He now has the cheapest launch system with the F9 and shortly, the worlds currently largest rocket, the Falcon Heavy. Both of these will beat any launch system unless nations like China and Russia simply subsidize even further, and dump on the global market. As such, more than 2/3 of his flights are Commercial, with many more expected once the F

The cost of the trip might only be half a mil, but the board and lodging on Mars would run to $1000's per night (minimum stay 8 months until the planetary alignment is right for the return trip). Got to make the money back somehow and it's not like there would be many alternative places to stay

minimum stay 8 months until the planetary alignment is right for the return trip

Technically you can just swing by on a minimum energy Hohmann ellipse and come right back. If you want to stay awhile its either gonna cost more fuel or time until you can set up another minimum fuel ellipse to come back.

If you're willing to burn a tiny tiny little extra fuel, you pass beyond mars orbit... so you jump a lander craft off on the way out, and rejoin on the way back in. Basically you plan a Hohmann pretending that Mars is in a slightly bigger orbit. Its actually a hell of a lot more complicated than this.

You can model stuff like this with the "orbiter" orbital mechanics simulator from the early 00s (and still going), or you can run the numbers, or just go intuitively.

From memory fooling around with this, the increased fuel in the main machine, and increased fuel in the lander craft, means you are not going to hang around very long... but from memory a couple days was not too unrealistic in terms of increased delta-v?

(minimum stay 8 months until the planetary alignment is right for the return trip)

That depends on whether you're committed to using an interplanetary transfer without thrust for the large majority of the time. If you can apply thrust the whole way, you have many more options open. Admittedly that means you're not going to be using conventional rockets, but that's pretty obvious in any case. The other advantage of a transfer under power is that it greatly shortens the time that people are at great risk from radiation and solar events like flares.

No, I think he's onto something. The trick is that once you get partway there, you'll be dead from some random solar flare's radiation. So, you won't need NEARLY as many amenities...and since you'll miss your flight back, that saves costs too! I can see the marketing now...

"Our customers love Mars so much, not a single one has decided to come back!"

with space stations at the top of both elevators, I suppose the trip could be made easier. Much less fuel would be required, since you do not have to break earth's atmosphere, or much of earth's gavity. Landing on Mars would be a non-issue, since you would just have to dock the space station at the end of the Mars space elevator.

Incidentally, fuel accounts for about 1% of the $50 million launch cost of a Falcon 9. That's what Elon Musk is trying to say. If you can get to a point where reassembling and reusing the launch vehicle costs as much as it's fuel, you can bring the cost of space flight down by two orders of magnitude.

No, the shuttle shows us that government procured hardware is the most expensive imaginable. After all, when assembling components for the shuttle, the order of business seemed to be 1. Find congressional district where reusable components could be built 2. build them there 3. figure out how to get the stuff where it actually needed to be in the first place. 4. Jobs! I mean Re-election! Er.....Profit!

Musk is almost certainly talking out of his ass. I'll plunk down 500 grand to go to mars right after my Phantom game console shows up. That being said, of all the people trying to make space flight more of a private endevour that it has been in the past, Musk has his name on the very short list of people in the "put up" rather than "shut up" category. He's putting real shit into real orbit, not not dragging tourists up for glorified X-15 flights (no slight to the Virgin / Scaled composites gang, but they're not doing heavy lift at the moment, but what they're doing is Steerman bi-plane rides on a much more awesome scale.)

People seem to be saying this because the Space Shuttle was fantastically expensive. The problem with that is that where were a lot of poor decisions that went into the shuttle (the ceramic heat shield, and the solid boosters) that we don't have to repeat in every new reusable launch system. Even in the '90s with Venture Star NASA was trying to move away from those technologies because they knew they were expensive and not beneficial.

There's nothing wrong with looking at your failures, seeing where they went wrong, learning from them, and trying again. The result is by no means a foregone conclusion. Can you imagine if the Wright Brothers had said "people have been trying to build airplanes for a hundred years and no one's succeeded so we may as well not even try." It's absurd to think we should give up on reusable space craft simply because the Space Shuttle didn't save money. Especially since the things that made it too expensive are so obvious and fixable.

Space elevators are stuff of dreams and the distant future... if they will ever be built. It is an interesting idea, but I'm still not convinced that the technology ever could be built to make them work... Carbon nanotubes and other claims about materials that might be able to withstand the tensile strength needed to get the job done withstanding. It certainly is something that needs the kind of technological progress we've seen over the past 200 years to continue on for another 200+ years.

That's actually rather optimistic, in my opinion. The catastrophic devastation that would be caused by a collapse is enough to prevent such a structure from ever being built. And unless we suddenly develop some kind of miracle material that makes nanotubes look ordinary, we'll never have the material needed anyway.

That's actually rather optimistic, in my opinion. The catastrophic devastation that would be caused by a collapse is enough to prevent such a structure from ever being built. And unless we suddenly develop some kind of miracle material that makes nanotubes look ordinary, we'll never have the material needed anyway.

The amount of damage caused by a falling cable would depend very much on its composition and geometry. A thin "tape" of high-strength material would rapidly slow down due to air friction, and a large proportion of it may simply burn up.

My first reaction to this was WTF, but I think I know the basic idea for his plan: pack as many people into a tin can as possible and send them flying. Couple that with frequent trips and the price drops even further. This is also probably going to involve asteroid/moon mining as well as fuel plants on Mars.

I am still very skeptical that he could get the cost down to 500k/person even with all of those improvements, but a 5m/person cost doesn't seem impossible to achieve with economies of scale.

LEO is nearly halfway to Mars surface in terms of delta-v [wikipedia.org].

So yeah, SpaceX is directly addressing the most important component of making Mars missions economically feasible.

If we can make access LEO a relatively cheap commodity, and make it so we don't have to lift every single thing that we're going to take to Mars all at once, and have a way to have robotic manufacture of fuel on Mars for the trip back, then I can totally see Musk's statement playing out.

It does all hinge on that first huge step though. Fortunately SpaceX is hardly neglecting that part, and progress is promising.

Is there any fuel on mars he can use? If not, how is it gonna get there? By rocket? Wouldn't it make more sense to just put enough in it for a round trip instead of wasting fuel to get a supply on mars? If there is fuel on mars, will he take some of it back to earth?

There is no fuel to be found, but you can make fuel from the atmosphere (CO2) and water (and lots of power from solar cells or fission). This has been proposed for decades now. For everything more than a one-off foot print mission it's certainly worth the effort.

Elon Musk may be a bit crazy, but he's not an idiot. In fact SpaceX has done lots of things meanwhile that were deemed plain impossible with the kind of money they had in hand. The crucial point will be if SpaceX will be a profitable company in the next years. If they manage to make sane profits I'm pretty well sure that Musk will put every penny into going to Mars. He's *that* crazy, really.

Elon Musk did say that he wanted to retire by living on Mars, and wants to make sure that he isn't alone there either. Given his age and what he has accomplished so far, he might just make it too.

It sure is a whole lot more sane than spending $30 billion dollars for a rocket that is half as powerful as the Saturn V and costs twice as much per pound as the Space Shuttle designed by the incredibly talented engineering firm known as the United States Senate. Which future do you really want to live in?

Ares V would have been a lot more than half as powerful, but most of that extra power would be lost with the inefficient solid rocket motors. The primary reason that Constellation failed (which incidentally will be a good part of the reason the SLS will fail) was the dependence on ATK's solid rocket motors.

Besides you and the original poster are really talking about payload to LEO, not power.

And it's worth noting here that the original poster is talking about SLS not Ares V which has a minimum legisla

So basically he's quoting the fuel costs for just the weight of the person and minimal life support for a one-way trip to Mars assuming a more efficient engine than we have today? That's nice, but it doesn't really capture the full extent of the costs for this trip.

Actually he said round trip but only after being done in volume and with R&D paid down, he did say towards the end that fuel costs were only $10-20/pound but already the Falcon Heavy would break the $1000/pound barrier - I assume this is to LEO. The capacity is only 40% of that to GTO which is almost the same as Mars transfer orbit, so more like $2500/pound but it still puts a 150 pound person on his way to Mars for $375k. The delta-v needed from Mars to Earth is lower, about as LEO so $150k for a $525k total. Of course you'll still need a lander and life support but I assume at the $500k price point Musk expects there is among other things a working Mars colony that can be expanded using local resources.

Remember that at this price point we could put 36,000 people a year on Mars if we dedicated NASA's budget to it, I'm thinking of a society that makes their own fuel, builds their own domes, produces their own solar panels and expands their own oxygen, food and water supply. The trip costs would be just the trip costs, I don't know how low you could get the lodging cost but surely it can't be that bad in volume. If you assume you start with a fully stockpiled ship on both ends and only think capsule+people+life support for the trip then it doesn't seem that unfeasible. Of course right now we have none of that but it'd be stupid for every mission to bring their own base and supplies forever.

If you could start to approach those rates you could possibly even make a living going to Mars, if you go for a 10 year trip and is a $100k/year software developer - which you can be from a cubicle on Mars - you can probably pay your own trip and boarding. Okay, the millionaire playboys will be first but if they can fund the R&D, get the volume up, cost down, fund the initial base then maybe you can get a snowball effect where lower costs lead to more people lead to lower costs. It won't solve earth's population problems but at $500k/person then colonizing Mars starts to look realistic. Once you're past a few thousand individuals they can procreate on their own too, though I suppose this is at odds with sending software developers;).

Send up a number of transport vehicles that run in an orbit between Mars and earth. It's not fast since it's using "gravity assist" trajectories (i.e. no fuel) all you need is the fuel for a shuttle to transfer the passengers to either the planet surface (or orbiting station).

Have a few of these transports in operation then you can have transfers every 4/12 weeks with the travel time of between 80 and 200 days depending on the orbital positions.

But to hitch a ride on the Mars cycler you would need to match it's velocity with it at some point on it's orbit. But at that point you have already obtained the correct trajectory to get to Mars anyway, so why do you need the cycler?

I haven't read any of the details of the idea, but I would guess it would be because you'd have a larger ship, more support equipment, etc., in the cycler and a small, limited capsule to go up and down. Therefore, you'd be using less propellant, since you're accelerating less mass back and forth.

He doesn't want to get it TO Mars, he wants to get it FROM Mars. There's enough CO2 and water there to produce your own fuel and oxidizer from local resources. Has been proposed (and demonstrated engineering-wise) since decades. This is not easy or cheap, but much easier and cheaper than to transport it there from Earth.

That's just the internet teaser price. Add in checked luggage, oxygen, in-flight meals, in-flight entertainment (plastic head phones), airport taxes, taxi fare, hotel at the destination, and a quarter every time you use the lavatory, and you'll regret ever taking the cheap no-thrills space line. Stick with the established major carriers.

"My vision is for a fully reusable rocket transport system"... NASA had that vision with the Space Shuttle, but even excluding all R&D and capital purchases, just the incremental costs per launch were orders of magnitude higher than $500k per seat. And that's just to LEO! OK, that's "halfway to anywhere", but maintenance is a bitch, the staff required is huge, on and on... NASA isn't a role model for efficiency, but I seriously doubt that the commercial sector is going to be able to outdevelop them

"My vision is for a fully reusable rocket transport system"... NASA had that vision with the Space Shuttle, but even excluding all R&D and capital purchases, just the incremental costs per launch were orders of magnitude higher than $500k per seat. And that's just to LEO! OK, that's "halfway to anywhere", but maintenance is a bitch, the staff required is huge, on and on... NASA isn't a role model for efficiency, but I seriously doubt that the commercial sector is going to be able to outdevelop them in just 10-15 years.

I thought the same a few years ago, but SpaceX just did everything right then. Hey, they developed a launcher (two actually), launchpads and a spacecraft, built *and* launched them for about the same amount of money as NASA or ESA need to build a single launchpad. ESA's ATV alone (without the launcher and everything else) did cost *more* than what SpaceX did spend altogether until now and ATV is just a one-way orbital transporter with no reentry capability.

Outdeveloping NASA and the other government-fed entities seems very much possible.

NASA hasn't gone too much beyond where they were in the mid 1960's and in some ways are going backward. The SLS isn't anything more than a scaled down version of the Saturn V made with used parts from earlier spacecraft, so if SpaceX is at the same level that NASA was in the mid 1960's... in 10-15 years they will be far ahead of anything NASA is doing at the moment. It is sad to say, but Skylab pretty much was the pinnacle of the manned spaceflight program and it has been going downhill since. They've improved some procedures, but NASA hasn't really done anything genuinely inspiring with the manned spaceflight program other than repair the Hubble telescope. The Shuttle flights looked cool.... but really?

It terms of daring to go where nobody has gone before, NASA just isn't where it is at any more. Heck, they can't even duplicate Alan Shepard's first flight, even though Richard Branson is trying to make that happen.

They already have. Dragon and Orion both started development in 2005. Dragon has already made one unmanned test flight and next month will fly an unmanned capsule to the ISS. Orion is planned to launch an unmanned test flight in two years. Dragon will carry 7 people and is planned to make the first crewed flight in 2016. Orion was originally supposed to support a 7 man crew, and then 4-6, and now it is 2-4, and the first flight will be 2020 or later. What part of out-developing and out-performing NASA are t

Nothing in this plan is beyond our current technology, and the costs would not be excessive. Falcon-9 Heavy launches are priced at about $100 million each, and Dragons are cheaper. With this approach, we could send expeditions to Mars at half the cost to launch a Space Shuttle flight.

Even more so when it's outside the realm of fantasy. But ignoring the probability of his quoted price. Ignoring the difference between putting humans on Mars vs putting robots on Mars. Ignoring the story here and taking a step back:

What do we do once we get there?

There's science to do. I get that. I'm a fan of science. But what exactly? And why do we want to go do it ourselves?
I've seen this boil down to two reasons: 1) Political showmanship. Getting people interested in science. All that fluff whi

I mean, obviously we can all see the logic in this as we have so much practice on a daily basis comparing the relative cost/value of cars based purely on gas money! Hell I think we'd all hard-pressed to find even a fraction of the transportationally-inclined population that gauged costs of automotive travel based on silly things like initial investment capital or maintenance fees!

It's only a logical leap (nay, barely a hop!) to assume that stellar travel will be just as reliable as our maintenance

Well, basalt contains Feldspar, which consists of Al2Si2O8 in combination with either calcium, sodium or potassium. The aluminium and oxygen certainly could be used in rocket fuel. Plenty of other Martian resources can be used for rocket fuel also. There are available perchlorates. There's also the CO2 rich atmosphere and available water. Using electricity (from nuclear or solar power) hydrogen can be obtained from the water, then the hydrogen can be used to make methane with the CO2.

To get into LEO the space shuttle requires 500,000 gallons of liquid propellant and 1 million pounds of solid propellant. How does he propose that he is going to go to mars an back while carrying supplies for the whole trip?

It's an obscenely idiotic claim. We're talking about something that would, no matter which way you cut it, cost billions. It's not even a vaguely believable line of bullcrap, but doubtless he'll scam some moron.

Why does it cost billions in order to travel to Mars? Explain that one then I might agree with you. If you are only suggesting it costs billions because the only way government bureaucrats have been able to figure out how to expand their empires to include a manned Mars mission is to ask for a trillion dollars from congress, then that is one approach.

The issue really is one of simply getting into low-Earth orbit cheaply. Drop that cost and getting to Mars can be done quite a bit cheaper. I don't know about a half million per seat, but it certainly could be done for less than a billion dollars a seat much less mutliples of a billion dollars. If mankind is ever going to get to Mars and doing anything realistic there, it simply must be cheaper.

The proof of this concept is simply letting Elon Musk have the legal ability to be able to try to do this, and to do so with his own money. Either he can get it done or not, but if idiots like you go around rewriting laws in Congress so people like him simply can't even try, we will never know if it is even possible. Space exploration is stagnating and the costs are escalating faster than inflation precisely because some groundhogs don't think there is any cheaper or easier way to get into space.

The energy cost of getting to Mars can be relatively low, if you're willing to take a long time and use an efficient transfer orbit. The problem with that is that the longer you have the humans in the vehicle the bigger it needs to be, and that pushes the cost up again. A short trip that's accelerating hard all the way will minimise muscle wasting and the food requirements. It will also require a huge amount of energy. A very efficient trip will take a significant fraction of a year. You can't expect h

Once you get into space you can also use other technologies for propulsion, like ion thrusters (low thrust.... but they can operate for a very long time with continuous thrust and insane specific impulse numbers) or even nuclear rocket engines like NERVA.

In theory, you can travel from the Earth to Mars in about six weeks and possible even less if you had the right engines. Yes, that takes a whole lot of energy.... but space is also full of a whole lot of energy too!

There are also things like Aldrin Cyclers and mission profiles that don't need to worry about how much mass is traveling between the Earth and Mars, so it becomes more like a cruise vacation on the journey complete with 5-star accommodations and staff along with entertainment. Those spaceships can literally be as big as you care... as large as any major cruse ship or larger. They can also be expanded to accommodate more passengers on each cycle or even have the construction crew "on staff" while in flight. It would be a bit of a trick to get the thing built initially, but the per passenger cost would be minimal and doesn't even need to worry about delta-v or even fuel at all and the staff can even be rotated out on each cycle. Food can be grown in such a vehicle, with air and water recycled as necessary... such a system is even being done on the ISS at the moment even though I'll admit it does need to improve to become practical on a larger scale. Solar arrays can be used for what energy needs such a vehicle might have. If you are going insane when running around a spaceship the size of a cruise ship, I can't help you out much. It may not look like a cruise ship, but then again stuff in space doesn't have to look like anything on Earth or even anything like what you've seen Hollywood come up with for spaceflight either.

In other words, it takes changing the notion of how things are done. The first few flights and getting the infrastructure set up are going to be expensive, but once that is built it doesn't have to be expensive for ongoing costs. The tough part is getting to and from the Earth to LEO or at worst to a "Earth Transfer Orbit" position. The sitting "as a sardine in a can" would only be for a couple days, and even then something like an Aldrin Cycler could be built to transfer between LEO and those other positions relatively near the Earth to get to the Earth-Mars cycler.

The idea that you are going to build a disintegrating pyramid starting from sea level at KSC bringing everything with you needed for the trip as you throw parts of your spaceship away is where the perception is flawed. Such a design methodology was useful in a wartime situation like how the Apollo program was built, but that doesn't need to be the only way to travel to other worlds. If anything, getting to the Moon with the Lunar Lander was about the limit of what you can do with chemical rockets flying on the disintegrating pyramid and Mars is simply unreachable. It is that mentality which creates the trillion dollar manned Mars missions too.

I have no problem with him trying, though I think it's a scam. But LEO ain't cheap, and then there's all the energy to get decent acceleration, and then there's building a craft that can sustain people for a considerable length of time. Half a million bucks is pure bullshit. Can't be done. I wouldn't believe it for half a billion, but that's certainly more believable than half a million. If that's the case, my net worth, if I cashed it all in, would be almost enough to get me to Mars, and I can tell you thi

Reusable spacecraft in space. The problem with every interplanetary mission plan is that it is a one time plan, or always involves launching the entire spacecraft form Earth every time. Why launch an interplanetary spacecraft to LEO multiple times? Launch it once and after that just launch fuel, supplies, and people. Maybe the a new lander or parts of a lander will need to be launched each time. Since, Ion engines are useful once in space fuel needs would be greatly reduced. A spacecraft that never lands should suffer very little wear and tear, so quit trying to build a single spacecraft to handle all phases of the travel plan. In addition, a reusable spacecraft that never lands can probably be built bigger and more comfortable than one that needs to survive re-entry.

1) Build one spacecraft that launches stuff to LEO.2) Assemble an interplanetary craft in LEO along with a lander.3) Launch supplies and crew to LEO. (could be multiple launches)4) Transfer crew to interplanetary craft.5) Set interplanetary craft on transfer orbit.6) Land lander.7) Do Stuff.8) Launch lander to interplentary craft.9) Return interplanetary craft to LEO.10) Transfer people to LEO landing craft.11) Repeat from step 3

This is one of the reasons I find any plan to de-orbit the ISS is stupid and wasteful. Even if there is no other science to be had, why waste a perfectly good transfer station for interplanetary travel? It would also probably be a good place to perform vehicle assembly since the interplanetary craft might makes sense to launch in multiple pieces or, if in a single launch, partially disassembled, so it does not have to be designed to survive launch stresses in a fully assembled state.

$10,000 for the giant cannon$999,990,000 for the criminal-negligence lawsuits when your budget-price spacestronauts suddenly yet inevitably explode on liftoff

Now, if you wanted to actually get them there and back alive, it will cost a few more zeroes than that.

(IE, design and implement a space greenhouse - including a space compost-recycling toilet - that runs perfectly for 18 months. However, if you can succeed at building one of those, you can probably amortise the cost by selling a few million of th

When I hear somebody say that you should colonize Antarctica before Mars, I have to say.... let me! The reason and the only reason you don't see cities in Antarctica (beyond something like McMurdo that doesn't have a permanent population) is politics. If you tried to set up a permanent settlement there and did something like drilled for oil, mined coal, or did other things on that continent to support a real city you would get your hand slapped so fast and put into prison that it would make your head spin

SInce a journey to mars will take 9-10 months with a convenient alignment between the planets, travel time would be at least 1.5 years, and the spacecraft would have to carry all its own supplies, it would have to be quite massive.

If you're going on a cross-country car trip, you don't fuel your car up with hundreds of gallons of gasoline at the start, do you?

One possible approach would be to set up "rest stops" stationed along the route the capsule would follow. If the capsule had the capacity to hold enough supplies that a missed station or even two wouldn't be fatal to the crew, all you'd need is sufficient fuel to travel from one station to the next plus some extra to maneuver. Rather than carrying a year and a half's worth of sup

And they'd have to have the extra fuel to stop at the stations, and then accelerate away again. AAAND they'd have the fun problem of having to time their departure to coincide not only with a reasonable alignment between Earth and Mars, but also enough of the "rest stops"... which would presumably be on their own independent orbits.

Probably something like this:1) Use cheap SpaceX rockets to reach LEO.2) Use multiple launches, carrying components of the Mars craft, the supplies, fuel, and crew on separate launches. This keeps you from needing a Giganto-rocket that ultimately couldn't lift as much as these separate launches anyway.3) Transfer to Mars orbit (which is easier than getting to LEO)4) Detach landing craft, land on Mars5) Re-fuel with fuel conveniently pre-manufactured by previous robotic missions (this is the only part not obvious to me how it would be done for whatever that's worth).6) Return to orbiter.7) Return to earth.

LEO is the big obstacle. Earth's gravity well is a killer -- it's the largest of any rocky body in the solar system. If we can make LEO cheap and easy -- which just happens to be Elon Musk's major goal with SpaceX -- then we've made the rest of the solar system significantly cheaper and easier.

Ah.... Earth-orbit rendezvous missions. The concept was originally dreamed up by none other than Werner Von Braun (and it wasn't even original then but he was in a position to make major decisions of that nature). That was the original plan for going to the Moon until the Lunar-orbit rendezvous plan was created.

In terms of a place to rendezvous around Mars, I think a landing on Phobos would be in order and would be a proven stable location that could be used for transfer between a low-Mars orbit and the M

Well, whatever you do, a 500 K$ per person price tag for the whole trip doesn't work. Even if you solve all major technical obstacles -- with that price, you're gonna be flooded with many thousands of applicants, whom you cannot all provide with a seat in a space ship, which means that basic supply-demand mechanisms will drive the price up.

Well, whatever you do, a 500 K$ per person price tag for the whole trip doesn't work. Even if you solve all major technical obstacles -- with that price, you're gonna be flooded with many thousands of applicants, whom you cannot all provide with a seat in a space ship, which means that basic supply-demand mechanisms will drive the price up.

You're mistakenly equating the cost to send someone to Mars and what YOU would pay to go to Mars. High demand and almost zero supply doesn't drive up what it costs SpaceX to do it, just what it costs you to pay SpaceX to do it.

Musk didn't say he could sell tickets to Mars for $500k in 15 years, he said he could send people to Mars for $500k. That's a HUGE difference, and means there is no question of demand or supply involved.

If you think that a $50 used moped is just as sexy as a Tesla Roadster and has the same performance characteristics, I suppose you are correct.

As for "taking tax dollars", the only tax money that was dumped into Tesla Motors was a loan program put together under the W. Bush administration originally intended to be for General Motors, but somehow Elon Musk was able to work it out that Tesla qualified for the same program and got some of the money. It was also a loan that had to be paid back.

As for the cost of the vehicle, if you don't like it, don't buy it. The only reason why Tesla is currently "losing money" is because they are ramping up the factory in Fremont, California (the former NUMMI plant) and getting ready for production of the Model S. Tesla Motors did make money off of the Roadster... not just a technical profit but a rather substantial amount. It was enough that Toyota decided to become one of those "venture capitalists" investing in Tesla... where I hope the Toyota corporation knows a thing or two about how to manufacture automobiles. Yes, they are just a minority owner in the company, but it also wasn't a tiny investment either.

The single most expensive part of a rocket is it's engine. After that it's the fuel tanks. There is no reason these things couldn't be reused without any significant refurbishment between trips, as long as you could recover them. Indeed, the space shuttle was able to save a lot of money by not replacing the engines after every launch. But they had an expensive experimental heat shield that needed extensive repairs after every launch. Add to that the ill-advised use of solid boosters, and you get what adds u

The single most expensive part of a rocket is it's engine. After that it's the fuel tanks. There is no reason these things couldn't be reused without any significant refurbishment between trips, as long as you could recover them. Indeed, the space shuttle was able to save a lot of money by not replacing the engines after every launch.

I'm detecting a little history rewriting, or subtle trolling. For anyone who doesn't get it, he's saying the opposite of what actually happened. With the exception that yes, he is correct engines are more expensive than fuel tanks.

At the moment, flight crew costs on most spacecraft are statistical noise, and the fuel costs are less than the catering budget for the public relations team and the people they are hosting at the launch. For the Space Shuttle it was the maintenance costs and the flight monitoring costs (analogous to the ATC crews for aircraft) that ate up most of the budget and had staff in the tens of thousands. Airlines wouldn't ever make a profit if they had to work under that kind of structure.

I would assume that most of the interplanetary portion of such a spacecraft would only have to survive one launch up through the atmosphere, rather than repeated ups and downs of, say, the Shuttle. There will always be the crew capsule itself, but for most of the vehicle - yes, it's mostly a matter of topping off the tank and turning it around. Or, not even doing that, if you use a Mars Cycler to go between the two.

The Space Shuttle suffered not from extreme abuse upon reentry, but rather from going through the bureaucratic grinding mill known as the United States Congress and the fact that it was envisioned to be "The One True Launcher" that would be used for everything and thus had to do everything possible in space and was built like a swiss army knife. It had to fly polar orbits, have cross-range ability to avoid "enemy" interception, carry a huge payload, and do all sort of other things that ate into its budget to meet the needs of every federal agency (not just NASA)...and that wasn't all. The cost of the orbiter started to go up because there were many early costs that were deferred until later because the bean counters felt they could go for a cheaper solution during the design stage and the early development that would end up costing more when it finally got to flight status. So many compromises were made on the Space Shuttle that frankly it ought to be a textbook example for how not to design a spacecraft and what happens when you let non-engineers become involved in key engineering decisions.

Seriously, don't use the Space Shuttle as an excuse for why reusable spacecraft fail. A much better design was with the "Crew return vehicle" that was designed and even had some metal bent, but never made it into space due to shifting priorities on the part of the U.S. Congress. That should say something too, where there hasn't been a single spacecraft designed by the NASA manned spaceflight program which has made it from the drawing boards to making an actual flight into space for over 40 years (the last one was the Space Shuttle). It hasn't been for a lack of ideas or even billions of dollars spent toward building something else, it is just that every time something is tried *something* goes wrong and the design is scrapped for the next better thing. That happened so many times that America doesn't even have a spacecraft any more for astronauts to use.